(1) Field of the Invention
This invention is directed toward sunshades and sunscreens useful for protecting a vehicle from the sun's rays. It is particularly directed toward external sunscreens attached to the roof or top of a vehicle.
(2) Description of Related Art
Internal sunscreens are a popular way to lower the internal temperature of a vehicle that is parked in the sun. The screens are typically installed just behind the front windshield and provide a way to keep the dashboard, steering wheel, and front seats from being too hot for a person to enter and sit down to operate the vehicle. The reduction in heat in the front of a vehicle provides for a faster cool down when the air conditioner is used, as the system does not have to cool down air conditioning ductwork first. Also, the vehicle driver can usually hold the steering wheel which can be too hot to comfortably touch when the sun directly shines on it.
The internal sunscreens fold into a compact shape such as by an accordion method, rolling up, or folding. This makes it convenient to store in the vehicle by setting it aside on the back seat or other area.
Internal sunscreens provide only a measure of protection from heating the vehicle interior. They are usually designed for the front windshield, and do not completely put the interior in a shady condition. A casual observation of parking lots in the southwest (where the sun in more intense) shows that it is desirable to obtain more complete shading. Vehicles are intentionally parked under shades from trees to obtain additional sun protection and lower the interior temperature, even though it may require a longer walk to a store or place of business.
Additionally, the sun will move and the effectiveness of a windshield sunscreen will be reduced when the sun's rays come in through the side windows of the vehicle.
Others have attempted to provide sunshades and external umbrellas for vehicles. For example US 20050242610 describes a sun cover that is magnetically attached to a car roof to cover all the vehicle windows. However, a fitted cover is needed for each car type in order for the magnetic attaching system to work. A single cover design that will shade a wide variety of vehicle models is not practical.
U.S. Pat. No. 6,012,759 describes a relatively permanent attachment on the vehicle roof that provides a pull out shade for the vehicle. This option is less desirable as the externally attached cover has a number of mechanical parts that will be exposed to the weather making reliability questionable. Also, there is no provision for shading side windows.
One embodiment of US20020139403 describes a center pole mount for a vehicle umbrella. This style of vehicle shade is less desirable as the umbrella is subject to wind and only provides shade for part of the vehicle. The other embodiment uses multiple attaching points.
U.S. Pat. No. 4,805,654 describes a rectangular sun shade with telescoping poles. The telescoping poles are not convenient to utilize and are awkward to collapse and store the shade in a compact space. The pole mount is unattractive and utilitarian, and fails to provide any sort of aesthetic appeal. Also, the shape of the shade does not provide for shading when the sun is at a low angle.
U.S. Pat. No. 5,795,012 describes a sun shade that is installed on top of a center mount. The center mount includes reinforcing ribbing for the sun shield that is permanently attached. This makes the installation of the shield is awkward and time consuming. Also, the deployment mechanisms used are overly complex for the simple need.
Successful external sunscreens are more difficult to effectively design then the interior ones, as seen by a lack of common use in the marketplace. Important matters of convenience have not been addressed in current designs. An external shade should be convenient and quick to install, it should be storable in a compact manner, any permanent mounting structure should have some aesthetic appeal, and it should provide a complete shading of the interior. It is also desirable for the sun shade to be built and designed at an affordable price.